Internal combustion engine

ABSTRACT

In an internal combustion engine having at least one cylinder defined by a cylinder head and a cylinder block, attaching means connecting said cylinder head to said cylinder block, said cylinder including a combustion chamber, intake and exhaust ports communicating with said combustion chamber and a connection means connecting said ports to a pipe, the improvement which comprises forming said pipe and connection means of at least two molded elements which are held on the engine in the required operational position by the attaching means connecting together said cylinder heads to said cylinder block.

Mutchler 123/4182 A 0 United States Patent 1 1 l 1 3,782,344 Schmuck 5] Jan. 1, 1974 [54] INTERNAL COMBUSTION ENGINE 3,099,983 8/1963 Orlando et a1 123/9038 x I 2,199,423 5/1940 Taylor 123/4182 A X [75] Inventor khan Schmuck Fe'lnbdch 2,492,582 12/1949 Klotsch et a1... 123 195 5 x Germany 3,064,634 11/1962 Tyce et a1 123/195 S X [73] Assignee: Motorenfabrik Hatz KG., Ruhstorf,

Germany Primary ExaminerAl Lawrence Smith [22] Filed y 12 1972 Att0rneyRoberts B. Larson [2]] Appl. No.: 252,915

[57] ABSTRACT [30] F i A li i p i i D In an internal combustion engine having at least one June 5 1971 Germany U P 21 29 738 1 cylinder defined by a cylinder head and a cylinder block, attaching means connecting said cylinder head [52] us CL 123/52 M 123/4169 123/41] to said cylinder block, said cylinder including a com- 123/193 123/195 181/33 bustion chamber, intake and exhaust ports communi- 51 1m. (:1 .f F02f 1/30 F02f 7/00 wing with said combustm chamber and a [58] Field of Search 123/4132 41.82 A means connecting Said Ports to a pipe the 123/195 5 v188 M 193 H 193 E 4169 provement which comprises forming said pipe and i 41.7 183/33 connection means of at least two molded elements i which are held on the engine in the required opera- [56] References Cited tional position by the attaching means connecting to- UNITED STATES PATENTS gether said cylinder heads to said cylinder block.

1 Claim, 4 Drawing Figures PATENTEU 11974 3-, 782.344

sum 2 BF 2 sob 52 INTERNAL COMBUSTION ENGINE FIELD OF THE INVENTION This invention relates to an internal combustion engine comprising at least two housing parts such as a cylinder head and a cylinder block connected together by means of attaching elements, one of which housing parts has intake or exhaust ports leading to the combustion chamber, and a pipe which may be either an intake or exhaust pipe connected to the ports by a connection means.

BACKGROUND OF THE INVENTION In the case of known internal combustion engine arrangements of this type, the common pipe or manifold in most cases is produced as a massive casting, the connecting piece of which is re-finished and attached to the corresponding supports of the machine housing. A cast pipe, however, represents an element which is expensive per se. Moreover, the refinishing and mounting of such a cast pipe will increase the cost even more. Beyond that, the weight of the cast pipe increases the total weight of the internal combustion engine and in addition increases the noises developing during operation of the machine.

It is the object of the invention to create a simpler and more economical pipe and to a manner of attaching it to the engine, while realizing at the same time a sound damping or deadening effect.

BRIEF SUMMARY OF THE INVENTION The object of the invention is achieved by forming the pipe and the connecting means leading to the ports of at least two molded elements, which elements are held on the engine in the required operational position with the aid of the attaching-means that connects the two housing elements, e.g., the cylinder head and cylinder block.

According to a further characteristic of the invention, it will be of advantage to additionally connect the two molded elements with one another at least in the areas requiring compactness, for example, by means of a welded seam or by beading.

In the case of the preferred embodiment of the invention, the arrangement is made in such a way that at least one of the molded elements constituting the pipe is clamped down firmly with its flat part between the two housing parts.

A very advantageous method of producing the pipe can be achieved according to another embodiment of the invention by the fact that each molded element consists of sheetmetal and is produced by a suitable forming process. In this case it will be practical to position at least one of the molded elements in such a manner that its section, clamped between the housing parts, projects beyond the periphery of the housing.

In the case of internal combustion engines with a cylinder head which has several cooling ribs on its periphery exposed to a cooling air stream, it is of particular advantage according to a further characteristic of the invention, to utilize the section of the molded element projecting beyond the housing part as a means for the conduction of cooling air.

An additional damping effect in the pipe itself will result according to another characteristic of the invention by forming the molded elements from multilayered sheetmetal, preferably sandwich plates. In this way the section of the molded element projecting beyond the periphery of the housing parts serves at the same time as a screening damping means for the noises radiated by the engine.

In addition, at least one opening is advantageously provided in the section'of the molded element projecting beyond the periphery of the housing element for the passage and/or support of a machine element seated in the housing part, as, for example, an injection nozzle.

BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the invention will be further described with reference to the accompanying drawings wherein:

FIG. 1 is a perspective view in partial section of two cylinder heads provided with an added intake pipe,

FIG. 2 is a top view of FIG. 1, and

FIGS. 3 and 4 are two cross-sections through the pipe and its attachment taken along line IIl-III and IV-IV, respectively, of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the embodiment illustrated, a two cylinder, aircooled internal combustion engine of known construction is shown. The cylinder heads 10 and 12, which lie individually beside one another, are connected firmly by means of attaching screws 14 to a cylinder block 13 containing two perpendicular cylinders (not shown in detail). In each cylinder head 10 or 12, input and output valves (not illustrated) are housed, which valves are driven by means of rocker arms, swivelably mounted in an upper part 16 or 18 of each cylinder head on both sides of a peg 20. The drive of the rocker arms is accomplished each time by an assigned push rod 22 which is driven up and down by the control gearing of the engine. Every upper part has been attached to the assigned cylinder head by way of screws 28 and has been closed by means of a lid 24 or 26.

The intake connection 12a of the cylinder head 12 leading to the combustion chamber in the cylinder,

ends in an opening 12b (See FIG. 4). A similar intake connection 10a with opening 10b also exists in the cylinder head 10. Both intake parts 10b and 12b are connected with an intake pipe by way of connection means, which pipe is formed and disposed in the manner described in the following paragraphs.

The intake pipe is made up of two thin-walled molded elements 30 and 32, which are punched from sheetmetal and formed for example in the cupping process. The flat section 30a of element 30 in its built-in state covers up the upper front sides of both cylinder heads 10 and 12 and is tightened to block 13 by means of attaching screws 14 during attachment of cylinders heads l0, 12 to the block. The upper parts 16, 18 are then placed onto section 300 and tightened by way of screws 28 to the cylinder heads. A part of the edge of element 30 is bent upward and formed into a half pipe 30b. The other element 32 is attached to element 30 at 32a by means of screws 14a. It is clear that in both elements 30, 32 suitable passages are provided for appropriate attaching screws. Details regarding this however have not been shown. A section of element 32, which likewise has been pulled upwards, constitutes the other half pipe 32b and in addition contains two salient portions 320 which constitute the connecting channels from pipe 30b, 32b to the ports 10b, 12b. Air entering lateral ports A or B of the pipe consequently can flow through the two channels 32c, the intake connections 10a, 12a and hence into the combustion chambers.

It could be advantageous to create an additional connection by means of a welded seam, etc., along the sealing places (on the pipe 30b, 32b) between the two pipe elements 30 and 32. No special attaching means are necessary, however, for attachment of the pipe elements on the engine, because the attaching screws between the housing parts also have as part of their function the attachment and centering of the pipe elements. The manufacture of the molded elements takes place preferably from multilayered sheetmetal or a sandwich plate. In this manner natural and foreign vibrations and noises in the pipe itself are dampened. The sections of the pipe elements reaching beyond the housing parts accomplish in addition a damping function for the noises which radiate from the cylinder block and cylinder heads. Beyond that, this projecting section 30a or pipe element 30 functions as a cooling conductive plate for the cooling air, which flows through the cooling ribs lr, l2r and the cooling channels k, 12k disposed inside and outside the cylinder heads, as becomes particularly clear from FIG. 3.

Also the molded elements are provided in a suitable manner with continuous or supporting openings for engine elements, such as injection nozzles 34 and protective casings 22a of the push rods.

Finally, it should be mentioned that the described design and attachment of the pipe represents only an illustrative embodiment of the invention. In deviation from this embodiment, a flat section 32a of the molded element 32 could have the same size as element 30 and could be attached with same means. Also, the exhaust pipe of the internal combustion engine could be formed and disposed in an analogous manner. The input ports A and B of the pipe, moreover, can be equipped with inserted air filters.

lt is claimed:

1. In an internal combustion engine having at least one cylinder defined by a cylinder head and a cylinder block, attaching means connecting said cylinder head to said cylinder block, said cylinder including a combustion chamber, intake and exhaust ports communicating with said combustion chamber and a connection means connecting said ports to a pipe, the improvement which comprises forming said pipe and connection means of at least two molded elements produced from multilayered sheet metal which are held on the engine in the required operational position by the attaching means connecting together said cylinder heads to said cylinder block, at least one of the molded elements being clamped firmly between the cylinder head and cylinder block, said clamped molded element projecting beyond the periphery of said connected cylinder head and cylinder block, the section of the molded element projecting beyond the periphery of the cylinder head and cylinder block serving as a screening damping agent for the noises radiating from the engine. 

1. In an internal combustion engine having at least one cylinder defined by a cylinder head and a cylinder block, attaching means connecting said cylinder head to said cylinder block, said cylinder including a combustion chamber, intake and exhaust ports communicating with said combustion chamber and a connection means connecting said ports to a pipe, the improvement which comprises forming said pipe and connection means of at least two molded elements produced from multilayered sheet metal which are held on the engine in the required operational position by the attaching means connecting together said cylinder heads to said cylinder block, at least one of the molded elements being clamped firmly between the cylinder head and cylinder block, said clamped molded element projecting beyond the periphery of said connected cylinder head and cylinder block, the section of the molded element projecting beyond the periphery of the cylinder head and cylinder block serving as a screening damping agent for the noises radiating from the engine. 